Strip material gripping and feeding devices for machines



Nov. 8, 1955 G. F. CLARK ET AL 2,723,117

STRIP MATERIAL GRIPPING AND FEEDING DEVICES FOR MACHINES Filed March 31, 1950 2 Sheets-Sheet l 16 l'lnunnunnnuuv INVENTORS sea/w: F dLARK JBHN G CLAR K m R1; w. CLARK M40 ATTOR/Vf) Nov. 8, 1955 G. F. CLARK ET AL STRIP MATERIAL GRIPPING AND FEEDING DEVICES FOR MACHINES 2 Sheets-Sheet 2 Filed March 31 1950 FIGS.

INVENTORS 650170,? 2' GC'LARK JOHN G. LARK R; HARD MAC'LARK ATTORNEY United States Patent Cfitice Patented Nov. 8, 1955 STRIP MATERIAL GRIPPING AND FEEDING DEVICES ron MACHINES George Frederick Clark, John George Clark, and Richard Walter Clark, West Drayton, England; said John George Clark and said Richard Walter Clark assignors to said George Frederick Clark Application March 31, 1950, Serial No. 153,208

Claims priority, application Great Britain, April 5, 1949 3 Claims. (Cl. 271-25) adjustment for material of various thicknesses.

A further object is to provide means whereby the feed of the material may be adjusted to suit various requirements.

With these and other objects in view the invention consists in providing a feeding device for strip material comprising a base on which is slidably mounted a carrier having a pivoted gripping plate connected by links to the arms of a pair of bellcrank levers, the other arms of the bellcrank levers having fulcrums on the base, links conmeeting the intermediate fulcrum of each bellcrank lever to levers having fulcrums on the base and means for moving the latter mentioned levers or links whereby the carrier will be moved rearwardly to raise the gripping plate from the strip material mounted on the carriage and spring means for returning the parts to their normal position to effect the feeding of the strip mtaerial forwardly the said material being gripped by the pivoted gripping plate to effect the feed of the strip material on the forward movement of the carrier.

The invention further consists in providing the slidable carrier with a rod extending longitudinally of the base and having its end threaded for adjusting nuts adapted to limit the movement of the carrier and the feed of the strip material by the nuts co-operating with the end wall of the base.

The invention still further consists in fitting at the rear end of the base a fulcrumed spring pressed plate adapted to permit forward or feed movement of the strip but to so engage the strip as to prevent rearward or backward movement of the strip.

One form of the invention will now be described with reference to the accompanying drawings in which:

Fig. 1 is a side elevation showing the relative position of the parts at the commencement of a feeding stroke;

Fig. 2 is a side elevation showing the relative position of the parts at the termination of a feeding stroke;

Fig. 3 is a plan of Fig.2;

Fig. 4 is a section on line X-X of Fig. 3, drawn to an enlarged scale, and showing in dot and dash lines the position of the gripper plate at the commencement of a feeding stroke, and in full lines the position of the gripper plate at the end of feed stroke;

Fig. 5 is an end elevation in the direction of the arrow A, Figure 2, the side springs being omitted and Fig. 6 is a section on line YY of Figure 3, parts being omitted.

As shown the gripping and feeding device for attachment to, for instance, a press tool or machine comprises a base casting 1 of substantially rectangular shape having 2 a longitudinally extending guideway 2 for a slidably mounted carrier Shaving a pivoted gripping plate 4 under which strip material such as strip metal indicated at a is adapted to be fed in the manner to be hereinafter described. The carrier 3 in the form of an L-shaped block is secured such as by Welding on a plate member 5. This plate 5 which is of rectangular shape is machined to provide opposite side surfaces 6 and a base surface 7 to slide in the guideway 2 of U-shape which is machined to provide co-operating side wall surfaces 8 and base surfaces 9. The carrier 3 is frictionally held in the guideway 2 by resilient means such by a spring plate 10 co-operating with machined surfaces 11 at each side of a longitudinal slot 12 cut in the guideway 2 the said spring plate being held by a centrally arranged bolt 13 screwed into the plate member 5 of the carrier 3. Alternatively the carrier 3 may be held by a spring pressed washer mounted on a downwardly projecting screw. In this case a coiled spring is mounted on the screw and the spring has abutments on the underside of the head of the screw depending from the carrier .and on the said washer. The base of the carrier 3 is provided with a rod-like extension 14 which extends longitudinally of the base and out through an aperture in the end wall 15 of the base casting 1. This rod 14 is threaded at 16 for the reception of lock nuts 17 adapted to engage the end wall 15 or a gate fitted thereto and limit the forward movement of the carrier 3. These nuts 17 can be adjusted to limit the feed of the strip material a which is positioned on a ground surface 18 on base casting 1 and passes through a slot 19 in the upstanding portion of the L-shaped carrier 3 and under the gripping plate 4. The carrier 3 is fitted with a horizontally arranged U-shaped bracket 20 to provide a pair or" arms 21 for the pivotal mounting of the gripping plate 4. This bracket 20 is conveniently secured adjustably to the vertical arm on the carrier 3 by bolts 22. The gripping plate 4 having a knife or inclined edge blade portion 23 is attached by bolts 24 to a carrier 25 formed with rod-like side extensions 26 at its upper end. These extensions 26 are movable in recesses 27 formed on the upper side of the arms 21 of the U-shaped bracket 20. Each recess 27 is shaped to provide a pair of seatings 28 and 29 the rear seating 29 being lower than the other and connected by a curved ramp which is struck from. a fulcrum point 34) of the gripping plate for the purposes to be hereinafter explained. The gripping plate 4 extends at each eiid beyond the body of its carrier 2:3 and these extensions provide the fulcrum points 30 which engage in recesses 31 formed in the underside of the arms 21 of the U-shaped bracket 25). To the rod-like extensions 26 or pivots of the carrier 25 are connected a pair of links 32 which are connected through the medium of a cross-shaft 3.3 to the arms 34 of a pair of bellcrank levers 35 which have their other arms 36 mounted on a cross-shaft 37 carried by the base casting 1. The intermediate fulcrums of the belicrank levers 35 are mounted on a cross shaft 33 and connected by a pair of links 39 to a cam operated cross-shaft 40 carried by levers 41 mounted on another cross-shaft 42 carried by the base casting 1. The cam operated shaft 40 is preferably fitted with a roller 43 t0 co-opcrate with a cam or the like on the press tool or machine. If desired the shaft 38 may be fitted with a roller so that it can be operated by the press tool. To each outward extension of the shaft 42 is secured one end of a coiled tension spring 44. The other ends of these springs are connected to the ends of the cross-shaft 38 forming the fulcrums of the bellcrank levers 35. To the rear end of the base casting 1 and just behind the bellcrank levers 35 is mounted a spring pressed plate 45 so fulcrumcd at its upper end at 46 in an upstanding fitment or gate 47 secured to the rear wall 15 of the base casting 1 as to engage the strip material a by its lower. edge the said mate rial being mounted on the said grounded surface 18 of the base casting 1. This lower edge is chamfered at 48 and the mounting of this plate 45 is such as to permit forward movement of the strip material but to prevent its rearward movement. The plate 45 is conveniently spring pressed by a coiled spring 4-9 mounted on a bolt 50 pivotally secured to the gate 47. This gate 47 may be fitted with a pair of adjustable guide members 51 to restrict the width of the gate opening to the width of, the strip material. The feeding device above described is formed with holes 52 so that it can be mounted by bolts or the like on, for instance, a press tool or machine and can be conveniently actuated by a cam or inclined edge of a plate secured to the press tool such as the downwardly movable plunger thereof indicated by the arrow I7, the said earn or inclined edge co-operating with the before-mentioned roller 43 on the cam operated shaft 40.

In operation, strip material indicated at a of any desired width and thickness adapted to be operated upon by a press tool is passed through the gate 47 and under the gripping plate 4 of the slidabiy mounted carrier 3 and upon the lowering of the cam plate indicated by the arrow [2 the inclined edge thereof will engage the roller 43 on the cam operated shaft 40 of the device and the links 39 arranged parallel with the base casting 1 will be moved rearwardly by the front levers 41 and the bellcrank levers 35 turning on their fulcrums carried by the base casting 1.. The carrier 3 of the gripping plate 4 will thus be moved rearwardly against the action of the coiled Springs 44 through the medium of the longer arms 34 of the bellcrank levers 35 and links 32 connected with rod-like ends 26 of the gripping plate carrier 25. This operation will turn the gripping piate 4 on its fulcrums 30 positioned at each end of the plate and the rod-like ends 26 will ride out of the recesses 2'7 and on the ramp surfaces to engage in the rear recesses 28 in the arms 21 of the U-shaped bracket 20 of the carrier 3 as shown in dotted lines in Fig. Thus the gripping plate 4 will be raised above the strip material a which latter will be gripped and held against rearward movement by the spring pressed plate 45 at the rear end of the base casting 1. Upon the raising of the cam plate connected with the press tool the coiled springs 44 wiil return the parts to their initial position and the strip material a will be gripped by the gripping plate 4 and fed into the press tool. It will be understood that the amount of feed and travel of the strip a can be varied by adjusting the lock nuts 17 on the rod member 16 connected with the carrier 3 of the gripping plate 4. Further the gripping plate 4 is so mounted that it will engage or move strips of various thicknesses.

What we claim is:

1. A gripping and feeding device for feeding strip material into machines, comprising a base, a carrier slidably mounted on said base, a gripper pivoted on said carrier, a bellcrank lever pivoted by one arm on said base, a link between the other lever arm and said gripper, a second lever pivoted on said base, a second link connecting the intermediate fulcrum of said bellcrank lever to said second lever and forming a parallelogram with said levers and base, means for actuating said second lever and second link to vary the angulation of the parallelogram to move the carrier rearwardly and swing the gripper from strip material mounted on the carrier, and spring means between the base and said parallelogram for returning the parallelogram to normal position to swing the gripper to engage the strip material and move the carrier to feed the strip forwardly with the carrier, said carrier comprises an L-shaped block having one arm upstanding from and the other arm secured to a plate member which is machined to provide opposite side and base slide surfaces, said base having a guideway of U-shape machined to provide cooperating side wall and base surfaces, said upstanding block arm being disposed transversely of said carrier and h ving a slot for passing the strip material, and said gripper being carried by said upstanding block arm, and wherein the pivot connecting the bell-crank fulcrum with the parallelogram forming link is extended at each end, the pivot connecting the second lever and base comprising a cross shaft, and said spring means comprises coiled springs disposed at each side of the device with one end of each spring connected to the respective pivot and the other end of each spring connected to said cross shaft.

2. A gripping and feeding device for feeding strip material into machines, comprising a base, a carrier slidably mounted on said base, a gripper pivoted on said carrier, a bell-crank lever pivoted by one arm on said base, a link between the other lever arm and said gripper, a second lever pivoted on said base, a second link connecting the intermediate fulcrum of said bell-crank lever to said second lever and forming a parallelogram with said levers and base, means for actuating said second lever and second link to vary the angulation of the parallelogram to move the carrier rearwardly and swing the gripper from strip material mounted on the carrier, spring means between the base and said parallelogram for returning the parallelogram to normal position to swing the gripper to engage the strip material and move the carrier to feed the strip forwardly with the carrier, and a U-shaped bracket supported by said carrier with the bracket arms extending substantially parallel With said base, said gripper comprising a blade attached to a body having laterally extending pivots at its upper end which are connected to said link, said blade extending at each end beyond said body and including fulcrurns engaging in recesses formed in the underside of the bracket arms, said arms having recesses formed in their upper sides and which are shaped to provide a pair of seatings to movably receive said laterally extending pivots, said pair of seatings being connected by a curved ramp having a radius struck from the pivotal axis of said blade fulcrums.

3. A gripping and feeding device as claimed in claim 2 wherein said actuating means is engageable with the pivotal connection between said second lever and second link.

References Cited in the file of this patent UNITED STATES PATENTS 1,007,236 Poirier Oct. 31,1911 1,305,343 De Smith June 3, 1919 1,407,699 Marian Feb. 28, 1922 1,690,512 Uttz Nov. 6, 1928 1,826,498 Bignell Oct. 6, 1931 1,968,479 Dickerman July 31, 1934 2,250,530 Hafecost July 29, 1941 2,278,921 Fischer Apr. 7, 1942 2,381,571 Buchan Aug. 7, 1945 2,397,833 Berton Apr. 2, 1946 2,444,706 Loew July 6, 1948 2,514,554 Nowelsky July 11, 1950 

